L8532中文资料POWER FACTOR CORRECTED  DIMMABLE LED DRIVER数据手册UTC规格书

描述 Description

The UTC  L8532 is a switch mode power supply controller intended for low to medium power single stage power factor (PF) corrected LED Drivers. The device is designed to operate in critical conduction mode (CrM) and is suitable for flyback as well as buck topologies. Constant on time CrM operation is particularly suited for isolated flyback LED applications as the control scheme is straightforward and very high efficiency can be achieved even at low power levels. These are important in LED lighting to comply with regulatory requirements and meet overall system luminous efficacy requirements. In CrM, the switching frequency will vary with line and load and switching losses are low as recovery losses in the output rectifier are negligible since the current goes to zero prior to reactivating the main MOSFETswitch. The device

特性 Features

a programmable on time limiter, zero current detect sense block, gate driver, trans-conductance error amplifier as well as all PWM control circuitry and protection functions required to implement a CrM switch mode power supply. Moreover, for high efficiency, the device features low startup current enabling fast, low loss charging of the VCCcapacitor. The current sense protection threshold has been set at 500 mV to minimize power dissipation in the external sense resistor. To support the environmental operation range of Solid State Lighting, the device is specified across a wide junctiontemperature range of -40℃ ~125℃ FEATURES   Very Low 24A Typical Startup CurrentConstant On Time PWM ControlCycle-by-Cycle Current ProtectionLow Current Sense Threshold of 500mVLow 2mA Typical Operating CurrentSource 500mA/Sink 800mA Totem Pole Gate DriverReference Design for TRIAC and Trailing Edge Line DimmersWide Operating Temperature RangeNo Input Voltage Sensing RequirementEnable Function and Overvoltage Protection